Medical therapy arrangement

ABSTRACT

A medical therapy arrangement, for applying electrical stimulation to a subject, includes a garment having electrodes at an inner surface. A control unit controls each electrode to work as one or more of anode, cathode or disconnected state, per a predetermined therapy stimulation program. Furthermore, the arrangement includes: at least one connection unit having a predetermined number of connection elements respectively electrically connected to the electrodes via separate connection lines being flexible and elastic and integrated into the garment; at least one connection board having a predetermined number of connection pads electrically connected to the control unit. The connection unit is an integrated part of the garment, with the connection board detachably attachable to the connection unit by a fastening element, such that the connection unit and the connection board, when interconnected, are positioned relative to each other in order to electrically connect the connection pads to mating connection elements.

FIELD OF THE INVENTION

The present invention relates to a medical therapy arrangement accordingto the preamble of the independent claim.

BACKGROUND OF THE INVENTION

The present invention relates in general to muscle relaxation, and moreparticular to muscle relaxation for spastic muscles in patients havinginjuries to the central nervous system (CNS) at least by using musclestimulation.

Injuries to the central nervous system (CNS) are difficult to treat andcure. Spastic paresis, which is a pathologically increased muscle tonuscaused by an injury to the central nervous system (CNS) is a significantobstacle for prevention of posturing and loss of mobility.

Today, therapeutic alternatives for the reversal of CNS injury symptoms,such as spasticity, are very limited. Therapies are constructed toprevent further loss of function, rather than alleviating the symptoms.No treatment has been found to truly give back function and, in the longrun, reversing the injury through muscle relaxation of spastic muscles.

In addition to the spasms themselves, musculoskeletal pain is a commonrelated complaint. Pain originating from dysfunction in themusculoskeletal system is in most cases caused by muscle spasms due tomuscular imbalance. If the pain is not treated properly, patients riskdeveloping chronic pain syndromes, conditions that are difficult tocure.

There are several techniques available to affect muscles in the humanbody. Electrical muscle stimulation (EMS), also known as neuromuscularelectrical stimulation or electromyostimulation is a commonly knownmethod for increasing muscle mass in specific areas, by providing anelectric current into the muscle causing contraction, which graduallyleads to increased mass in the treated muscle.

Trancutaneous Electrical Nerve Stimulation (TENS) is closely related toEMS, but instead of stimulating muscles to contract, electricstimulation is used to indirectly treat pain, by distracting the brainthrough the stimulation of other body parts. In U.S. Pat. No. 4,580,572,a garment for electrical monitoring of sites or electrical stimulation,such as EMS is disclosed.

However, none of the currently known muscle stimulation techniques issuited to provide for targeted muscle relaxation. Hence, a newarrangement including a garment allowing for increased muscle relaxationwould be advantageous.

In general, the parameters of the EMS current signal may be chosen whichresemble the physiology of the body. The signals in the nervous systemmay be compared to current impulses (stimuli) to the synapses. When acertain amount of stimuli has occurred, signal substances are excreted.

Generally, a phasic EMS-stimulus is given with a frequency rangingbetween 2 and 50 Hz, and having a duration between 5 to 300microseconds.

Muscle relaxation in spastic muscles gives the possibility to inducecontrolled functional muscle contraction in chosen relaxed muscles. Thefrequency needed to induce muscle contraction is higher than thefrequency used for optimal antagonist muscle relaxation (20 Hz/30 μs).Stimulation frequencies for functional muscle contraction are rangingfrom 25 to 50 Hz and the duration needed is between 50-300 μs.

The pulsed EMS current signal is controlled by at least the followingparameters; pulse frequency, pulse duration, pulse strength.

Experiments have shown that muscles start to contract at a pulsefrequency of approximately 15 Hz to approximately 35 Hz, at whichfrequency range the central nervous system feels the presence of thecurrent signal. The present inventor has realized that by choosing afrequency as low as possible, but still detectable by the centralnervous system, the discomfort for the patient is reduced, while theautomatic relaxation of the spastic antagonist muscle is taken care ofby the central nervous system. A higher frequency than approximately 35Hz would lead to shortening of the stimulated agonist muscle andtherefore activation of the stretch reflex in the antagonist musclewhich is not desired, since this would lead to a reciprocal spasm of theagonist muscle.

The pulse duration of the current signal is selected such that itresembles the pulse duration of nervous signals. For example, a pulseduration of approximately 5 to 60 microseconds, such as 30 μs, has beenfound to be suitable. However, even shorter pulse duration could beadvantageous. Too long pulse duration of the EMS current signal does notcorrespond to the neurophysiologic parameters of the body.

Furthermore, longer pulse duration may also increase the risk of muscleshortage, which is not desired.

Since the spastic muscle behavior in CNS injured patients differsgreatly, the professional skills of a neuromuscular system specialist isrequired for calibrating the system before use, such that the correctagonist muscles are provided with EMS electrodes and jointscorresponding thereto are provided with vibrator devices. Every chosenmuscle stimulation is paired with an anatomically relevant jointstimulation in order to strengthen the desired relaxation effect.Furthermore, the parameters of the pulsed EMS current signal need to beselected, which parameters may differ between patients.

The above-described stimulation and calibration techniques are furtherdisclosed in WO-2011/067327, which relates to a system and garment formuscle relaxation of a spastic muscle, and is assigned to the applicantof the present application. In particular the system is adapted to causemuscle relaxation by reducing muscular spasticity through stimulation ofjoints and muscles. The system consists of a garment with electrodes, ahardware unit and software controlling the stimulation.

WO-03/006106 relates to a method and apparatus for electricalstimulation to selected tissues via an array of electrodes positioned onand/or in the body. Each electrode may be connected either as anode,cathode or neither to provide discrimination between stimulated andnon-stimulated regions of tissues of the body.

WO-2011/079866 relates to an apparatus for external activation ofparalyzed body parts by stimulation of peripheral nerves.

US-2011/0152968 relates to an orthosis for a gait modulation system, andfinally, U.S. Pat. No. 7,072,721, that relates to an electrode vest forelectrical stimulation of the abdomen and back

Today, when performing external electrical stimulation therapy, it iscommon to use electrode patches provided with an adhesive for attachingthe electrodes to the patient's skin. These electrode patches aredisposable, and it is often very time-consuming to attach the electrodesand to connect the electrical cables to each of the electrode patches.

The object of the present invention is to achieve an improvedstimulation therapy arrangement, which is more user-friendly and lesstime-consuming to use, than the presently used adhesive electrodes.

As an electrical stimulation therapy preferably must be applied at least30 minutes in order to give prolonged effect, one further and importantaspect of the stimulation therapy arrangement is that it is comfortableand easy to use for the wearer.

SUMMARY OF THE INVENTION

The above-mentioned object is achieved by the present inventionaccording to the independent claim.

Preferred embodiments are set forth in the dependent claims.

One great advantage of the arrangement according to the presentinvention is that it is easy to use. This is, among other things,related to that the control unit that includes the pulse generatingcircuitry, is easily attached to the garment by some few manual steps byattaching the connection board to a connection unit which is integratedinto the garment.

The garment is elastic and is intended to be tightly worn by thepatient. The garment is ready for use in a user-friendly way forexternal electrical stimulation therapy of muscles. Electrodes, e.g.silicone-electrodes, are arranged at the inner surface of the garment,the surface facing the patient's skin and in contact to the patient'sskin. The electrical connections connecting the electrodes to connectionunits are flexible and elastic.

The garment is made from materials chosen such that the garment may bewashed in conventional laundry machines.

In particular the garment includes electrical connections adapted toconnect the electrodes to one or several connection units, which do notinfluence the overall flexibility/elasticity of the garment. This isachieved, according to one embodiment, by integrating, e.g. by weavingsilver threads into elastic bands or ribbons or into a piece of elastic.

In another embodiment instead an insulated conductor is integrated (e.g.weaved) into a piece of elastic.

The connection units are integrated into the garment, they have e.g. aflat extension, and they are flexible. Preferably, they are made from arubber material and are provided with a magnetic material. In particulareach connection element of the connection unit is provided with a magnetbeneath the rubber material and arranged such that a connection pad maybe attached at the upper surface and held in place by the magnet. Theconnection pad is naturally also provided with a magnetic materialenabling the attachment.

The connection pads are arranged at a flexible flat board having themagnetic material arranged at predefined positions in order to exactlyconnect each of the connection pads to a mating connection element ofthe connection unit. The connection board and the connection unit areheld together by the magnetic forces created by the magnetic material atthe respective parts.

According to one embodiment both the connection unit(s) at the garmentand the connection board(s) are made of a flexible material, which is animportant aspect making the garment more comfortable to wear.

According to the invention the control unit is adapted to controlconnection of each of the electrodes to be in the state of acting asanode, cathode, or being disconnected.

By this arrangement it is e.g. possible to stimulate two muscles bythree electrodes if the applied stimulation pulses are separated intime, i.e. one of the electrodes are used for both muscles. Thus, thecontrol unit enables a very flexible control of the application of thestimulation pulses and by using short simulation pulse durations verycomplex stimulation programs may be used in that many muscles and musclegroups may be covered during the therapy.

The control unit preferably applies a so-called open-loop control, i.e.no feedback is used to control the applied current/voltage. Theadvantage of not using feedback is that in case an electrode temporarilyloses contact to the skin, or the contact area between electrode surfaceand skin decreases, the current density of the remaining contact surfacenot should incur pain.

The amount of energy supplied to the patient via the electrodes is muchlower than the energy levels used for by devices for pain relief. Onerisk, or drawback, with such devices is that the applied energy mightstimulate the muscle to contract.

The level of the stimulation energy used in connection with the presentinvention is much lower than used for example in the device described inWO-03/006106.

SHORT DESCRIPTION OF THE APPENDED DRAWINGS

FIG. 1 is a schematic block diagram illustrating the medical therapyarrangement according to the present invention.

FIG. 2 is a schematic cross-sectional view of a part of the connectorboard and connector unit according to an embodiment of the presentinvention.

FIG. 3 is a schematic block diagram illustrating another embodiment ofthe medical therapy arrangement according to the present invention.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION

The present invention will now be described with references to theappended drawings.

With references to FIG. 1, the present invention relates to a medicaltherapy arrangement 2, for applying electrical stimulation to a human oranimal subject, comprising a garment 4 adapted to be tightly arranged atsaid subject, and provided with a plurality of electrodes 6 at the innersurface which are adapted to be in electrical contact to the skin of thesubject.

The arrangement further comprises a control unit 8 which is adapted toprovide each electrode 6 to work as one or many of anode, cathode orbeing disconnected, in accordance with a predetermined therapystimulation program.

At least one connection unit 10 is provided which comprises apredetermined number of connection elements 12 being respectivelyelectrically connected to the electrodes 6 via separate connection lines14, which are flexible and elastic. And, at least one connection board16 is provided which comprises a predetermined number of connection pads18 being electrically connected to the control unit 8.

The connection unit 10 is an integrated part of the garment 4 andpreferably arranged such that the connection elements 12 are accessibleto establish electrical connections to the connection pads 18 of saidconnection board 16. In that regard the connection board 16 isdetachably attachable to the connection unit 10 by a fastening means 20,such that the connection unit 10 and the connection board 16, whenattached to each other, are positioned in relation to each other inorder to electrically connect the connection pads 18 to matingconnection elements 12.

According to one embodiment the fastening means 20 is adapted todetachably attach the connection board 16 to the connection unit 10 bymagnetic forces. FIG. 2 is a schematic cross-sectional view of a part ofthe connector board 16 and the connector unit 10. In the figure it isshown that the magnetic forces are created by magnetic material, in thefigure indicated as separate magnets, arranged at predefined positionsof the connection board 16 and the connection unit 10, respectively. Inthe figure the magnets are arranged behind each of the pads 18 andelements 12 in order to secure the electrical connection. As analternative, the magnets may be arranged e.g. behind every second padand element or at positions close to the pads and elements.

The positions of the magnets at the connection board 16 and at theconnection unit 10 ensure that these are correctly positioned inrelation to each other. In order to further improve the positioning, oneor many protuberances and mating indentations (not shown in the figure)may be arranged at the connection board and connection unit,respectively.

As an alternative the fastening means 20 comprises mechanical meanswhich is adapted to detachably attach the connection board to theconnection unit. These mechanical means may e.g. comprise one or manyVelcro straps arranged to provide for the necessary pressure between theconnection board and connection unit in order to establish electricalconnection between the pads and elements. The mechanical means may alsobe embodied by some kind of snap connection.

Preferably, the connection unit 10 has an essentially planar extensionand is made from a flexible material, e.g. a flexible rubber material.

Also, in accordance with one embodiment, the connection board 16 has anessentially planar extension and is made from a flexible material, e.g.a flexible rubber material.

However, it is advantageous that, in particular the connection unit 10,is made from a flexible material, in order to make the garmentcomfortable to wear, but it is also possible, within the scope of thepresent invention, that the connection board 16 and/or the connectionunit 10 is made from a rigid material. According to one embodiment theconnection unit is made from a flexible material but the connectionboard is made from a more rigid material, e.g. from a suitable plasticmaterial.

The connection board 16 and the connection unit 10 have essentially thesame size. In one exemplary embodiment the shape is approximatelyrectangular having a length in the interval of 8-12 cm, a width of 1.5-3cm and a thickness of 0.25-1.5 cm.

Naturally, other sizes and shapes are possible, e.g. circular andelliptical, within the scope of the invention as defined by the appendedclaims.

The connection lines 14, that connect each electrode 6 to a respectiveconnection element 12, are flexible and elastic such the wearer of thegarment may move unimpededly.

According to one embodiment the connection line 14 is included into apiece of elastic into which an electrical conductor is integrated. Thisis achieved e.g. by weaving conducting threads, e.g. made from silver,into the piece of elastic.

As an alternative the connection line 14 is an insulated conductor beingdirectly integrated, e.g. by weaving, into the material of the garment.

The control unit 8 is preferably a separate unit in relation to theconnection board 16, and that the connection pads 18 are connected tothe control unit 8 via an electrical cable 22. According to oneembodiment the control unit 8 comprises a stimulation pulse generator,an energy source, a storage means, an input/output unit and a couplingunit. The energy source, typically being a battery, e.g. a rechargeablebattery, is adapted to energize the circuitry of the control unit, e.g.the stimulation pulse generator. The predetermined therapy stimulationprogram is stored in the storage means and specific instructions relatedto the specific patient to be treated is input by the physician via theinterface. The input/output unit may include one or many buttons and adisplay, e.g. a touchscreen. The control unit is preferably attached tothe garment wearer by some kind of strap in a position where it iseasily accessed but not prevents movements.

In accordance with another embodiment the control unit instead is anintegral part of the connection board, and then the connectingelectrical cable is obviated.

The control unit is preferably adapted to apply an open-loop controlwhen controlling the application of stimulation pulses. I.e. nofeed-back is used which is advantageous in order to avoid that higherstimulation current is applied in the situation where an electrodeloses, or has less, contact to the skin.

The garment is preferably made from a predetermined number ofinterconnectable parts. The reason is that the garment then is easier toput on. Each part is then provided with a connection unit that in turnis connected to the electrodes.

For some patients only a part of the body has to be subjected tostimulation, e.g. an arm or a leg. In that case a garment is used thatis adapted to enclose that part. And, for other patients, the entirebody has to be enclosed by the garment in order to gain full effect ofthe therapy.

An overall requirement of the garment is that it may be tightly arrangedat the body to secure that the electrodes are in contact to the skin ofthe patient. The garment must be able to be washed in a normal laundrymachine. Preferably the garment comprises a synthetic fiber made from apolyurethane-polyurea copolymer, e.g. spandex or elastene. According toan embodiment, the garment comprises five major textile and supportmaterials. Elastic spandex for areas covering muscles and, embedded inthis spandex, muscle electrodes for skin contact; firm elastic spandextextile in joint areas to induce joint stability and specific skincontact of embedded muscle and vibration (if included) electrodes; andVelcro to interlock the garment parts and also induce joint stabilityand electrode skin contact. Zippers are placed in the different garmentparts to enable simple dressing and use of the garment. Padding andother supportive materials are placed between the textile layers toenhance stability and electrode skin contact.

In order to provide for a perfect garment fit for each patient, eachgarment may be tailor made for each patient. Hence, each patient may beindividually measured. Based on the calibration made by the specialist,the therapist chooses which muscles to stimulate and therefore inducemuscle relaxation of corresponding spastic muscles. The tailor madegarment is produced and the control unit is programmed with thenecessary parameters such as to perform a vibrator (if included) and EMSstimulation in the prescribed manner.

The electrodes are arranged at the inner surface of the garment and musttherefore be flexible to adapt to the skin surface. According to oneembodiment the electrodes are silicone-electrodes. The number ofelectrodes is naturally dependent upon the therapy to be applied, butpreferably at least ten electrodes are included, often much more.

According to another embodiment the control unit comprises a sensingunit adapted to receive electrical signals, e.g. EMG-signals, sensed byone or many of said electrodes. The received signals may then beanalyzed and used to improve the therapy. According to one aspect thesensed electrical signals are used to decide which therapy to be usedand then apply that therapy in accordance with an open-loop controlledstimulation therapy.

According to another aspect, it would also be possible to apply thearrangement in a closed-loop controlled simulation therapy where theapplied stimulation energy is adapted in dependence of sensed electricalsignals.

In a further embodiment the arrangement also provides for combinedelectrical and vibration therapy. This embodiment is schematicallyillustrated in FIG. 3. The same references used in FIGS. 1 and 2 applyhere as well. To use a combined electrical and vibration therapy hasproven an advantageous therapy and in accordance to this embodiment aplurality of vibration units 7 are arranged at the garment, e.g. at theinner surface of the garment, and wherein each vibration unit beingconnected to the connection unit via a flexible and elastic vibrationunit connection line 15. The vibration units may also be arranged at theouter surface of the garment and apply the vibrations through thegarment material.

Different types of vibration units may be used, e.g. based uponpiezo-technology, a so-called DC-motor, or a solenoid based unit.

Preferably the relation between the number of electrical stimulationelectrodes and vibration units is 2:1. However, even fewer vibrationunits may be used.

The present invention is not limited to the above-described preferredembodiments. Various alternatives, modifications and equivalents may beused. Therefore, the above embodiments should not be taken as limitingthe scope of the invention, which is defined by the appending claims.

1. A medical therapy arrangement (2), for applying electricalstimulation to a human or animal subject, comprising a garment (4)adapted to be tightly arranged at said subject, and provided with aplurality of electrodes (6) at an inner surface of the garment (4) andwhich are adapted to be in electrical contact to the skin of thesubject, a control unit (8) adapted to provide each electrode (6) towork as one or many of anode, cathode or being disconnected, inaccordance with a predetermined therapy stimulation program, whereinsaid arrangement further comprises at least one connection unit (10)provided with a predetermined number of connection elements (12) beingrespectively electrically connected to said electrodes via separateconnection lines (14) being flexible and elastic and being integratedinto the garment, at least one connection board (16) provided with apredetermined number of connection pads (18) being electricallyconnected to the control unit (8), and that said connection unit (18) isan integrated part of said garment (4), wherein said connection board(16) is detachably attachable to said connection unit (10) by afastening means (20), such that said connection unit (10) and saidconnection board (16), when attached to each other, are positioned inrelation to each other in order to electrically connect the connectionpads (18) to mating connection elements (12).
 2. The medical arrangementaccording to claim 1, wherein said fastening means (20) is adapted todetachably attach said connection board (16) to said connection unit(10) by magnetic forces.
 3. The medical arrangement according to claim2, wherein said magnetic forces are created by magnetic materialarranged at predefined positions of the connection board (16) and theconnection unit (10), respectively.
 4. The medical arrangement accordingto claim 1, wherein said fastening means (20) comprises mechanical meanswhich is adapted to detachably attach said connection board (16) to saidconnection unit (10).
 5. The medical arrangement according to claim 1,wherein said connection unit (10) has an essentially planar extensionand is made from a flexible material.
 6. The medical arrangementaccording to claim 1, wherein said connection unit (10) is made from aflexible rubber material.
 7. The medical arrangement according to claim1, wherein said connection board (16) has an essentially planarextension and is made from a flexible material.
 8. The medicalarrangement according to claim 1, wherein said connection board (16) ismade from a flexible rubber material.
 9. The medical arrangementaccording to claim 1, wherein said connection line (14) is included intoa piece of elastic into which an electrical conductor is integrated. 10.The medical arrangement according to claim 9, wherein said conductor isintegrated by weaving conducting threads, e.g. made from silver, intosaid piece of elastic.
 11. The medical arrangement according to claim 1,wherein said connection line (14) is an insulated conductor beingdirectly integrated into the garment's material or into a piece ofelastic.
 12. The medical arrangement according to claim 1, wherein saidcontrol unit (8) is a separate unit in relation to said connection board(16).
 13. The medical arrangement according to claim 1, wherein saidconnection board (16) is connected to the control unit (8) via anelectrical cable (22).
 14. The medical arrangement according to claim 1,wherein said control unit (8) is an integral part of said connectionboard (16).
 15. The medical arrangement according to claim 1, whereinsaid garment (4) is adapted to enclose a part of or the entire body ofthe subject.
 16. The medical arrangement according to claim 1, whereinsaid garment (4) comprises a synthetic fiber made from apolyurethane-polyurea copolymer, e.g. spandex or elastene.
 17. Themedical arrangement according to claim 1, wherein said electrodes (6)are silicone rubber electrodes.
 18. The medical arrangement according toclaim 1, wherein said control unit (8) is adapted to apply an open-loopcontrol when controlling the application of stimulation pulses.
 19. Themedical arrangement according to claim 1, wherein said control unit (8)comprises one or many of a stimulation pulse generator, an energysource, a storage means, an input/output unit and a coupling unit. 20.The medical arrangement according to claim 19, wherein said control unitcomprises a sensing unit adapted to receive electrical signals sensed byone or many of said electrodes (6).
 21. The medical arrangementaccording to claim 1, wherein said arrangement comprises a plurality ofvibration units (7) arranged at said garment (4), and wherein eachvibration unit (7) being connected to said connection unit via aflexible and elastic vibration unit connection line (15).